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Quest-ce que le Principe de Précaution? Zoroaster: When in doubt, abstain. Removal of the handle of the Broad Street water pump in London in 1854, an action that then stopped an epidemic of cholera (see, e.g., Charles E. Rosenberg, 1962). This measure followed documented (but unconfirmed) suspicions by John Snow, a physician and much revered early epidemiologist, that the cause of the disease originated in the pump. (Afterwards, a detailed investigation determined that, more than 20 feet underground, a sewer pipe passed within a few feet of the well.) Vorsorgeprinzip – the forecaring principle – introduced into German environmental law in the 1970s.

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Quest-ce que le Principe de Précaution? The U.S-Canada Great Lakes Water Quality Agreement: Such a strategy [a phase out of all toxic persistent substance] should recognize that all persistent toxic substances are dangerous to the environment, deleterious to the human condition, and can no longer be tolerated in the ecosystem, whether or not unassailable scientific proof of acute or chronic damage is universally accepted. Science-based regulation (the National Environmental Policy Act, the Clean Water Act, the Occupational Safety and Health Act, the Federal Food, Drug, and Cosmetic Act, …) The U.S. Food Safety System stipulates that conservative risk management decisions be implemented when safety information on a hazard in a food is substantial but incomplete.

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Quest-ce que le Principe de Précaution? Despite this widespread use, however, the Precautionary Principle remains controversial and is often the object of acrimonious debates. Advocates argue that it provides potential victims a safeguard against sloppiness or manipulation in science-based regulation. But critics say that it gives undue veto powers to environmental extremists to block technological progress and opens the door to lobby groups to foster trade protectionism. Admittedly, in its present form the Precautionary Principle is subject to a wealth of interpretations. The potentially high stakes involved would make a clarification of its meaning and use quite timely.

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Quest-ce que le Principe de Précaution? When an activity raises threats of harm to human health or the environment, precautionary measures should be taken even if some cause-and-effect relationships are not fully established scientifically.